Plastic bag with reinforced sides

ABSTRACT

A plastic bag includes a body having overlapped first and second layers. The overlapped first and second layers define a receiving space. The body further includes two sides respectively having a first corrugated portion and a second corrugated portion. Each of the first and second corrugated portions includes a layer unit having eight layer sections. Each of the eight layer sections is a portion of one of the first and second layers.

BACKGROUND OF THE INVENTION

The present invention relates to a plastic bag and, more particularly, to a plastic bag with reinforced sides by corrugated portions.

Plastic bags are widely used in daily lives for various purposes including receiving articles, garbage, etc. The structural strength of plastic bags is often limited by their material in view of costs and, thus, has a limited load capacity. Although officially discouraged from the environmental and ecological aspects, use of plastic bags for carrying articles is inevitable.

FIG. 5 shows a conventional so-called T-shaped plastic bag 2 having a body 20 and two handles 21 extending upward from two ends of a top of the body 20, presenting a shape similar to a T-shirt. Each of two sides of the plastic bag 2 has a corrugated portion 22 extending inward and interconnected to one of the handles 21 and to a bottom of the body 20. The load imparted from the articles received in the plastic bag 2 to the bottom of the body 20 can be distributed to the corrugated portions 22. Each corrugated portion 22 generally includes a recessed section 221 formed in one of the sides of the body 20 and having a two-layer structure (a single fold). Thus, the body 20 has four layers including the recessed section 221. However, the load capacity of the plastic bag 2 is still limited, for the structural strength of the recessed section 221 having a single fold is not high enough.

Thus, a need exists for a plastic bag with reinforced sides for supporting purposes.

BRIEF SUMMARY OF THE INVENTION

The present invention solves this need and other problems in the field of plastic bag structure by providing, in a preferred form, a plastic bag including a body having overlapped first and second layers. The overlapped first and second layers define a receiving space. The body further includes two sides respectively having a first corrugated portion and a second corrugated portion. Each of the first and second corrugated portions includes a layer unit having eight layer sections. Each of the eight layer sections is a portion of one of the first and second layers.

The plastic bag according to the preferred teachings of the present invention does not simply increase the number of the layer sections of the layer units of the first and second corrugated portions. Due to overlapping of the first and second layers, after forming the layer units of the first and second corrugated portions by folding the first and second layers, the number of the layer sections of each layer unit is doubled.

The present invention will become clearer in light of the following detailed description of illustrative embodiments of this invention described in connection with the drawings.

DESCRIPTION OF THE DRAWINGS

The illustrative embodiments may best be described by reference to the accompanying drawings where:

FIG. 1 shows a perspective view of a plastic bag according to the preferred teachings of the present invention.

FIG. 2 shows a perspective view of a semi-product of the plastic bag of FIG. 1.

FIG. 2A shows an enlarged top view of a circled portion of FIG. 2.

FIG. 3 shows a perspective view of an initial state of the plastic bag according to the preferred teachings of the present invention.

FIG. 4 shows a perspective view of an intermediate state of the plastic bag according to the preferred teachings of the present invention.

FIG. 5 shows a perspective view of a conventional plastic bag.

All figures are drawn for ease of explanation of the basic teachings of the present invention only; the extensions of the figures with respect to number, position, relationship, and dimensions of the parts to form the preferred embodiments will be explained or will be within the skill of the art after the following teachings of the present invention have been read and understood. Further, the exact dimensions and dimensional proportions to conform to specific force, weight, strength, and similar requirements will likewise be within the skill of the art after the following teachings of the present invention have been read and understood.

DETAILED DESCRIPTION OF THE INVENTION

With reference to FIGS. 1, 2 and 2A, a plastic bag according to the preferred teachings of the present invention can be utilized for shopping and for receiving articles, garbage, or any objects in daily lives. The plastic bag includes a body 1 made of plastic material and includes overlapped first and second layers 11 and 12 defining a receiving space for receiving purposes. The body 1 further includes two sides respectively having a first corrugated portion 14 and a second corrugated portion 15. Each of the first and second corrugated portions 14 and 15 includes a layer unit 16 having eight layer sections. Each of the eight layer sections is a portion of one of the first and second layers 11 and 12. The structural strength of the body 1 at the sides is, thus, enhanced.

It can be appreciated that the plastic bag according to the preferred teachings of the present invention does not simply increase the number of the layer sections of the layer units 16 of the first and second corrugated portions 14 and 15. Due to overlapping of the first and second layers 11 and 12, after forming the layer units 16 of the first and second corrugated portions 14 and 15 by folding the first and second layers 11 and 12, the number of the layer sections of each layer unit 16 is doubled. As an example, each layer unit 16 includes eight layer sections when first and second layers 1 and 2 are utilized.

In a case that the body 1 includes a third layer overlapping the overlapped first and second layers 11 and 12, the layer unit 16 of each of the first and second corrugated portions 14 and 15 includes twelve layer sections.

In manufacture, the first and second layers 11 and 12 overlap each other with two lateral sides of the first and second layers 11 and 12 joined together along joining lines L1 and L2 (FIG. 3). The overlapped first and second layers 11 and 12 are folded in two, obtaining a four-layer structure. Next, the four-layer structure is joined along a joining line L3 (FIG. 4). Then, the waste material Al outside of the joining line L3 is cut away.

The term “join” used herein means engagement by hot melting or by bonding or gluing at proper locations. The joining lines L1, L2, and L3 can be continuous or discontinuous.

With reference to FIG. 2, after removal of the waste material A1, each of two sides of the four-layer structure is folded inward to form a recessed portion 17. Thus, each of the first and second layers 11 and 12 are folded twice, obtaining an eight-layer structure. The semi-product shown in FIG. 2 can be cut along a cutting line L4 to obtained two symmetric handles 18 (FIG. 1). Top edges of the layer sections of each recessed portion 17 are joined to form a top edge 18A for each handle 18. The first and second layers 11 and 12 are also joined at a bottom 18 of the body 1. The layer unit 16 of each of the first and second corrugated portions 14 and 15 can be joined to the bottom 18 of the body 21 by such as pressing.

Thus since the invention disclosed herein may be embodied in other specific forms without departing from the spirit or general characteristics thereof, some of which forms have been indicated, the embodiments described herein are to be considered in all respects illustrative and not restrictive. The scope of the invention is to be indicated by the appended claims, rather than by the foregoing description; and all changes which come within the meaning and range of equivalency of the claims are intended to be embraced therein. 

1. A plastic bag comprising: a body including overlapped first and second layers, with the overlapped first and second layers defining a receiving space, with the body further including two sides respectively having a first corrugated portion and a second corrugated portion, with each of the first and second corrugated portions including a layer unit having eight layer sections, with each of the eight layer sections being a portion of one of the first and second layers.
 2. The plastic bag as claimed in claim 1, with the body further including a bottom, and with the layer unit of each of the first and second corrugated portions joined to the bottom of the body by pressing.
 3. The plastic bag as claimed in claim 1, with the body further including a third layer overlapping the overlapped first and second layers, with the overlapped first, second, and third layers defining the receiving space, and with the third layer forming additional four layer sections in each of the first and second corrugated portions. 